Histological variations in liver of freshwater fish Oreochromis mossambicus exposed to 60Co gamma irradiation

The irradiation effect of 60Co at the three dose level of 3 mGy, 30 mGy and 300 mGy on the histology of liver of the freshwater fish Oreochromis mossambicus was investigated. The liver of O. mossambicus was dissected out and processed for light microscopy studies. 60Co exposed O. mossambicus were found to result in several alterations in the histoarchitecture of liver. The alterations included mild congestion of blood vessels, structural alteration, cellular swelling, vacuolation and necrotic liver cells, indicating a definite response to 60Co irradiation. The results suggest that the liver of O. mossambicus exposed to 60Co were structurally altered with increasing dose levels. It is to record that alteration in the liver does not affect the physiology, behaviour or lethality of the individuals. Self regulating mechanisms would have influenced the liver to remain sustained. To confirm the same further studies in the direction by increasing dose level is required. - Highlights: ► Fish Oreochromis mossambicus irradiated to the dose of 3 mGy, 30 mGy and 300 mGy. ► Histoarchitecture of liver altered with increasing dose levels of 60Co. ► Alteration in the liver does not affect the physiology, behaviour or lethality. ► Self regulating mechanisms might have prevented from Lethality. ► HSI index value for exposed group reported (<1) with low dose exposure of 60Co.